Modified natural resin ester copolymers and process of making same



Patented Aug. 15, 1950 MODIFIED NATURAL RESIN ESTER COPOLY- MERS ANDPROCESS OF MAKING SAME John B. Rust, Montclair, N. J assignor, by directand mesne assignments, of one-half to Montclair Research Corporation, acorporation of New Jersey, and one-half to Ellis-Foster Company, acorporation of New Jersey No Drawing. Application March 15, 1946,

Serial No. 654,794

14 Claims.

This invention relates to modified copolymers of natural resin esterssuch as rosin r copal esters and to the process for the preparation ofthe same. tion or copolymerization products obtained by reacting: (a)Natural resin acid ester compositions comprising a polyhydric alcoholesterified with natural resin acids and a polycarboxylic acid monoesterof a beta-unsaturated monohydric alcohol containing from 3 to 4 carbonatoms and (b) polymerizable compounds containing 1 or more C=CH2 groups.

It is an object of this invention to provide resinous compositionscomprising modified natural resin acid esters, wherein the principalconstituent is a highly unsaturated polymerizable ester consisting of apolyhydric alcohol esterified with a monoalkenyl ester of apolycarboxylic acid and an unsaturated resinous acid such as abieticacid or the unsaturated acids derived from rosin, copals, and othernatural resins, which are heat advancing and which may be converted intoinsoluble, infusible masses by the application of heat.

It is a further object of this invention to provide a copolymer which issoluble in drying oils and which may be oil-reactive.

It is a still further object of this invention to provide modified rosinesters which may be heated with phenolicresins, alkyd resins, natural Vresins, and the like to secure various types of resins which when cookedwith drying oils give fast drying, non-yellowing coating compositions.

Other objects of this invention will become apparent from the followingdescription:

There is disclosed in .my copending applications Serial No. 531,117,filed April 14, 1944, now Patent No. 2,398,668, April 16, 1946, andSerial No. 534,531, filed May 6, 1944, now Patent No. 2,398,669, April16, 1946, (entitled Modified Rosin Esters and the Process of MakingSame) of which the present application is a continuation in part,modified rosin esters consisting of a polyhydric alcohol esterified witha monoalkenyl ester of a'polycarboxylic acid and rosin.

Unsaturated polymerizable esters, having the highly unsaturatedmonoalkenyl ester ofa polycarboxylic acid attached directly to thepolyhydric alcohol in addition to the unsaturated natural resin acid maybe represented by the general formula Barr- DA); where R is the acidradical oi a natural resin, P is the radical of a polyhydric alcoholP(0H)n, D is a dicarboxylic acid radical, A is the radical Moreparticularly it relates to addiof a beta-unsaturated monohydric alcoholor 3 to 4 carbon atoms and a: is a positive number less than 11. Theyare formed by esterifying the polyhydric alcohol with sumcient naturalresin acid and dicarboxylic acid monoester to react with all thehydroxyl groups of the polyhydric alcohol. While the essential ester isof the type represented, the proportions of reactants may be such as toform a simple natural resin-polyhydric a1- cohol ester along with theunsaturated ester.

These unsaturated esters are readily capable of combining withpolymerizable unsaturated compounds of the type.

thus providing oil-soluble resins which are exceedingly high melting.Such a combination may take place through the unsaturated groups of theester with the unsaturated group of the C=CH2 compound, thus givingproducts most useful to the art.

The products of this invention ar prepared by heating together in asuitable reactor a highly unsaturated polymerizable ester (a polyhydricalcohol esterified with a monoalkenyl ester of a polycarboxylic acid andan unsaturated resin acid such as rosin) and a polymerizable compoundhaving at least one C=CH2 group, at

150-250 C. under reflux until there is substantially no condensation ofvapors, thus indicating completeness of reaction. Also, in practice itis at times useful to employ a peroxide catalyst such as benzoylperoxide and the like to facilitate the rate of addition.

The products of this invention are light-colored, hard, brittle resinswhich possess high softening points and low acid numbers. The pro-;portion of C=CH2 compound to unsaturated resin ester being preferably ina range of 5% to depending upon the properties desired, although between10% and 25% of the C=CHz compound is generally preferred. These resinsare compatible with and may be blended with drying oils, celluloseesters, phenolic resins, urea resins, melamine resins, polystyrene,polyacrylic acid esters, polymethacrylic acid esters, and the like, thusgiving products particularly adapted to drying oil varnish formulations,nitrocellulose lacquer formulations, moldings, laminated products, andthe like.

Numerous formulations of the unsaturated, polymerizable ester may beemployed in the invention. In my copending patent applications,

I have disclosed and claimed a number of polyhydric alcohols, resinacids. and also a number of dicarboxylic acid monoesters of unsaturatedmonohydric alcohols containing 3 to 4 carbon atoms. Thus, as startingmaterials I contemplate the following constituents of unsaturatedresinous esters wherein these materials are so reacted as to give thedesired unsaturated polymerizable ester.

Thus. as polyhydric alcohols, I may use pentaerythritol,polypentaerythritol, glycerol, polyglycerols, ethylene glycol,polyethylene glycols, dihydroxy ethoxy benzene, sorbitol, mannitol andthe like.

As resin acids, I may use rosin, abietic acid, and resin acids from thesaponification of copals and other natural resins. I

Among the monoalkenyl esters of polycarboxylic acids, I may usemonoallyl maleate, monoallyl itaconate, monoallyl citraconate, monoallylphthalate, monoallyl fumarate, monoallyl succinate, monoallyl sebacate,monoallyl adipate, and the like. In place of allyl alcohol I may alsouse methallyl alcohol, crotyl alcohol, methyl vinyl carbinol and thelike.

Diels-Alder products of conjugated dienes such as cyclopentadiene,isoprene, butadiene, and the like, with unsaturated dicarboxylic acidssuch as maleic anhydrlde, fumaric acid and the like may be used as thepolycarboxylic acid in the formation of the heretofore mentionedmonoalkenyl esters.

The compounds above listed are presentative of those which may be usedin the process of the present invention and should not be construed asbeing limiting since numerous other polyhydric alcohols, unsaturatedmonohydric alcohols, polycarboxylic acids, and unsaturated resin acidsmay be employed in carrying out the teachings of this invention by thoseskilled in the art.

The unsaturated resin esters heretofore described may be combined with anumber of unsaturated compounds which are capable of being polymerizedand which maybe represented by the general formula CHz=CR-R', where R Irepresents hydrogen or a methyl group and R is a negative radical suchas aryl, acyl, carbalkoxy, acyloxy, acyloxymethyl, halogen car-boxyl,hydroxyl and the like. Among such typical derivatives may be used vinylacetate, acrylic acid esters of saturated monohydric alcohols, styrene,ethylene glycol ester of monoallyl maleate, di-

' ethylene glycol ester of monoallyl maleate, saturated monohydricalcohol esters of monoallyl maleate, saturated monohydric alcohol estersof monoallyl fumarate, glycerol ester of monoallyl maleate,pentaerythritol ester of monoallyl maleate, polyhydric alcohol esters ofmonoallyl phthalate, polyhydric alcohol esters of monoallyl sebacate,diallyl maleate, diallyl phthalate, diallyl sebacate, dihydroxy ethylether of hydroquinone (monoallyl maleate ester) etc.

The following examples are given in the way of illustration only andshould not be limited, as numerous deviations are possible within thescope of the invention.

Example 1.-1500 parts of WW rosin and 193.2 parts of glycerol are heatedtogether in a 3-liter, 3-neck flask equipped with a stirrer, thermometerand air condenser at ZOO-240 C. for 6 hours. 156 parts of monoallylmaleate are added and heating continued at 200-220 C. until all of thewater of reaction is eliminated. A hard,

softening point of 98 C. (Softening point of ester gum=89 C.) Theproportions of reactants used in making this ester composition areapproximately 2 moles of glycerol with moles of rosin and 1 mole ofmonoallyl maleate.

30 parts of the above resin and 60 parts of bodied linseed oil areheated together rapidly to 300 C., and the temperature held at 290-300C. for 28 minutes until the resulting varnish base could be drawn into astring 18"-24" in length. It is thinned with 90 parts of VM and Pnaphtha, and 0.% lead as lead naphthenate and 0.06% cobalt as cobaltnaphthenate added based on the oil. The varnish air-dried to a tack-freefilm in 5% hours. After 24 hours, the dried varnish film-possessed aSward' rocker hardness of 39. The dried film softened slightly in tapwater during 24 hours.

A. 90 parts of the resin of Example 1 and 10 parts of styrene are heatedtogether in a 3- neck flask equipped with a stirrer, thermometer, andwater cooled condenserto 200" C. The temperature is then increased to250C. over a period of 6 hours. All condensation of monomeric styrenehad ceased. An exceedingly light-colored resin is obtained whichpossesses an acid number of 19.2 and a ring and ball' softening point of114 C.

30 parts of the above resin and parts of bodied linseed oil are heatedtogether rapidly to 300 C. and the temperature held at 290-300" C. for18 minutes. The resulting varnish base could be drawn into a string18"-24" in length. It is thinned with 90 parts of VM and P naphtha, and0.6% lead as lead naphthenate and 0.06% cobalt as cobalt naphthenateadded based on the oil. The varnish air-dried to a tack-free film in 4hours. After 24 hours, the dried varnish film possessed a Sward rockerhardness of 47. The dried fllm softened slightly in tap water during 24hours.

B. 90 parts of the resin of Example 1 and 10 parts of distilled vinylacetate are heated together in 3-neck flask equipped with a stirrer,thermometer, and water condenser to 200 C. and held at this temperaturefor 17 hours. There is no further condensation of monomeric vinylacetate.- A light-colored resin is secured which possesses an acidnumber of 21 and a ring and ball softening point of 103 C.

C. 120 parts of the resin of Example 1 and 40 parts of styrene areheated together in a 3- neck flask equipped with a stirrer, thermometer,and water cooled condenser to 200 C. The temperature is then increasedto 250 C. over a period of 6% hours. All condensation of monomericstyrene had ceased. An exceedingly lightnumber of 21.5 and a ring andball softening brittle, light-colored resin is secured which pospoint of113 C.

30 parts of the above resin and 60 parts of bodied linseed oil areheated together rapidly to 300 C. and held at 290-300 C. for 20 minutes.The varnish base could be drawn into a string 18"-24" in length. It isthinned with parts 200-240 C. for 6 hours.

of VM and P naphtha. and 0.6% lead as lead naphthenate and 0.06 cobaltas cobalt naphthenate added on the oil. The varnish air-dried to atack-free film in 5 hours. After 24 hours, the dried varnish filmpossessed a Sward rocker hardness of 43. The dried film softenedslightly intap water after 24 hours.

E. 122.5 parts of the resin of Example 1, and 22.5 parts of diallylmaleate are heated together in a 3-neck flask equipped with a. stirrer,thermometer, and air-condenser to 200 C. The temperature is slowlyraised to 250 C..and held for 8% hours. A light-colored, clear resinforms which possesses an acid number of 19 and a ring and ball softeningpoint of 118 C.

Example 2.--1000 parts of WW rosin and 145 parts of technical gradepentaerythritol are 1 mole of pentaerythritol with 3% moles rosin andmole monoallyl phthalate.

A. 127.5 parts of the above resin and 22.5 parts of monomeric styreneare heated together in a 3-neck flask equipped with a stirrer,thermometer, and water-cooled condenser to 200 C. The temperature isincreased to 250 C. over a period of 7 hours. All condensation ofmonomeric styrene has ceased. A light-colored, hard resin forms whichpossesses an acid number 9.2 and a ring and ball softening point of 107C.

B. 120 parts of the resin of Example 2 and 20 parts of diallyl maleateare heated together in'a 3-neck flask equipped with a stirrer,thermometer, and air condenser to 200 C. The temperature is increased to250 C. over a period of 8 hours. A light-colored, hard resin is producedwhich possesses an acid number of 14.5 and a ring and ball softeningpoint of 112 c.

C. 135 parts of the resin of Example 2 and 15 parts of diethylene glycolester of monoallyl maleate are heated together in a 3-neck flaskequipped with a stirrer, thermometer, and air condenser to 200 C. Thetemperature is increased to 250 C. over a period of 4 hours. Allcondensation of monomeric allyl ester had ceased. A light-colored, hard,brittle resin is obtained which possesses an acid number of 10 and aring and ball softening point of 114 C.

30 parts of the above resin and parts of bodied linseed oil are heatedtogether rapidly to 300 C. Heating is continued at 290-300 C. for 25minutes. A light-colored varnish base is secured, which could be drawninto a string 18"-24" in length. It is thinned with paris of VM and Pnaphtha and 06% lead as lead naphthenate and 0.06% cobalt as cobaltnaphthenate added upon the oil. The resulting varnish air dried to atack-free film in 4% hours, and after air drying for 24 hours possesseda. Sward rocker hardness of 45.

Example 3. parts of kauri having an acid number of 62, 20 parts of WWrosin and 11.3 parts of glycerol are heated together at 200- 240. c. ina 3-neck flask equipped with a thermometer, stirrer, and outlet tubeleading to a water-cooled condenser. A hydroxyl-containing ester isobtained having an acid number of 12.

20 parts of monoallyl maleate are added and heating continued at ZOO-220C. for an additional 4 hours. A hard brittle resin is formed whichpossesses an acid number of 17 and a ring and ball softening point of117 C. The softening point is raised when the natural resin ester isheated with styrene as in Example 2-A.

Having thus set forth my invention, I claim:

1. A resinous composition comprising the co polymerization product, atbetween C. and 250 C. of a polymerizable compound containing a group,and an unsaturated natural resin acid ester of the general formula (R0)H r-(DA) where R. is the acyl radical of an unsaturated natural rwinacid, P is the residue of a polyhydric alcohol P(0H)1. in which n is aninteger greater than one, D is a dicarboxylic acyl radical onecarboxylic group of which is esterified by A, A is a 2-alkenyl group of3 to 4 carbon atoms,

and a: is a positive number less than n, the

amount of polymerizable compound containing a group being from 5% to 60%of said ester.

2. A resinous composition comprising the copolymerization product atbetween 150 C. and 250 C. of a polymerizable compound containing'a,

group, and an ester composition comprising a. polyhydric alcoholesterified with rosin and a dicarboxylic acid monoester of abeta-oleflnic monohydric alcohol of 3 to 4 carbon atoms, the amount ofrosin and dicarboxylic acid monoester being suflicient to react with allthe hydroxyl groups of the polyhydric alcohol, the amount ofpolymerizable compound containing a C=CH1 group being from 5% to 60% ofsaid ester.

3. A resinous composition comprising the copolymerization product atbetween 150 C. and 250 C. of a polymerizable compound containing agroup, and an ester composition comprising glycerol esterified withsufficient rosin and a dicarboxylic acid monoester of a beta oleflnicmonohydric alcohol containing from 3 to 4 carbon atoms to react with allthe hydroxyl groups of the glycerol, the amount of polymerizablecompound oontaining a group being from 5% to 60% of said ester.

4. A resinous composition comprising the copolymerization product atbetween 150 C. and 250 C. of a polymerizable compound containing agroup, and an ester composition comprising pent-aerythritol esterifiedwith sumcient rosin and a dicarboxylic acid monoester of a beta olefinicmonohydric alcohol containing from 3 to 4 carbon atoms to react with allthe hydroxyl groups 7 of the pentaerythritol, the amount ofpolymerizabie compound containing a group being from to 80% of saidester.

5. A resinous composition comprising the copoiymerization product atbetween 150 C. and 250 C. of a polymerizable compound group, and anester composition obtained by reacting substantially 2 moles of glycerolwith 5 moles ofrosin and 1 mole of monoallyl maleate, the amount ofpolymerizable compound containing a group being from 5% to 60% of saidester.

6. A' resinous composition comprising the copolymerization product atbetween 150 C. and 250 C. of a polymerizable compound containing agroup, and an ester composition obtained by reacting substantially 1mole of pentaerythritoi with 3% moles of rosin and moles of monoallylphthalate, the amount of polymerizable compound containing a group beingfrom 5% to 60% of said ester.

7. The resinous composition of claim 1 wherein the polymerizablecompound containing a roup is s yrene.

8. The resinous composition of claim 1 wherein the polymerizablecompound containing a group of diallyl maleate.

containing a 5 group is vinyl acetate.

9. The resinous composition 01' claim 1 wherein the'polymerizablecompound containing a 10. A composition as set forth in claim 1 in whichthe dicarboxylic acid is saturated.

11. A composition as set forth in claim 1 in which the dicarboxylic acidis an alpha-unsaturated alpha beta dicarboxylic'acid.

12. The process of making a resinous composition which comprises heatingat between 150 and 250 C. a mixture of a. polymerizable compoundcontaining a the dicarboxylic acid is an alpha-unsaturated alpha. betadicarboxylic acid.

. JOHN B. RUST.

REFERENCES CITED The following references are of record in the file oi!tliis patent:

UNITED STATES PATENTS Number Name Date 2,195,362 Ellis -Mar. 26, 19402,230,242 Kropa Apr.- 21, 1942

1. A RESINOUS COMPOSITION COMPRISING THE COPOLYMERIZATION PRODUCT ATBETWEEN 150*C. AND 250*C. OF A POLYMERIZABLE COMPOUND CONTAINING A